Improvement in teeth for grain-drills



C, E. PATRIC. Seed Dri ll Teeth.

Patented Feb. 1, 1870.

UNITED STATES- PATENT OFFICE.

O. E. PATRIO, OF MACEDON, NEW YORK.

IMPROVEMENT IN TEETH FOR GRAIN-DRIL'LS.

Specification forming part of Letters Patent No. 99,467, dated February 1, 1870.

To all whom it may concern.-.

Be itknownthat I, CHARLES E. PATRIO, of Macedon, county of Wayne, State of New York, have invented certain new and useful Improvements in the Teeth of Grain-Drills; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this specification, in which 'Figurel is a side elevation of my invention, showing the link b broken away, and indicating the position of th'e'tooth when thrown back in dotted lines. Fig. 2 is a top View.

Similar letters indicate corresponding parts.

My invention consists in a novel arrangement of parts, whereby the spring is applied in suchmanner that it is expanded when the tooth is thrown backward, thus enabling me to dispense with one piece of the combination heretofore used, while at the same time the spring, when the tooth is in a proper working position, lies parallel with the drag-bar, and may be even partly incased by it, thus reducing the device to its most compact form. Another point of improvement is that in my construction I can use a spring'of almost any desired length, and by so doing obviate all liability to breakage of either the spring or its connecting devices, which has hitherto been a serious objection to this class of tooth. Its nature will be understood by reference to the drawings and specification.

To enable others skilled in the art to make and use my invention, I will describe its construction and operation.

I use the ordinary draw-bar, B, Figs. 1 and 2, composed of two straps, to which I pivot the tooth A, in the usual manner. At a convenient distance from the tooth I pivot upon the draw-bar the locking-stud a, having upon its upper end the bossesz' i,projecting equally from each of its sides. a

'It is obvious that, instead of the bosses i 2' being formed upon the stud a, they may be attached to the links b b, or a pin may be inserted in bar B in such manner as to serve as a stop to limit the forward throw of the links and stud. When the tooth is in proper position, the bosses rest upon the edge of the drawbar, as shown. 7

Pivoted to the lockingstud are the links b b, Fig. 2, which are secured in the same manner, at their opposite ends, to a lug, a, Fig. 1, cast upon the tooth. A little in front of the locking-stud a the straps of the draw-bar are spread somewhat, Fig. 2, to admit between them the spring d, which is attached at one end to a pin put through the draw-bar, and at theother to an eye at the upper end of the locking-stud. The upper pivot of the looking -stud rests slightly above a line drawn through the lower pivot and the pivot at the opposite end of the links b b, Fig. 1. rangement of the links and locking-stud forms a knuckle-joint placed nearly on a deadcenter and held in position by the spring dv The degree of resistance of the tooth to obstructions is governed by the relative position of the pivoted centers 0 0 0 and the tension of the spring d.

The stud a may be made in the form of a bell-crank and the spring attached to the other arm; or it may be placed below the draw-bar; but I prefer the arrangement shown. It may be desirable to provide a stop, either upon the links or the draw-bar, to limit the backward throw of the tooth.

The operation of my invention is as follows: When the tooth encounters an obstruction, it remains rigid until the pressure becomes too great, when the locking-stud suddenly yields, swinging over to the position shown in the dotted lines, or to any intermediate position, expanding the spring d and allowing the tooth to slide over the obstacle. When the obstruction is passed, the spring returns the tooth to its place through the medium of the links b b, whereby the spring (I both holds the stud in its locked position and also readjusts the tooth after having passed the obstruction.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The arrangement of the draw-bar B, links b b, lockingstud a, andspring d, substantially as and for the purpose set fort l 2. The locking-stud a, links b b, and bosses or stops i i, in combination with the open or divided drag-bar B, operating substantially as set forth.

, O. E. PATRIG.

Witnesses:

WM. S. LOUGHBOROUGH, H. N. HEMINGWAY.

This ar- 

